The objective of this research is to characterize tissue from its intrinsic ultrasonic scattering properties. Measurements of ultrasonic scattering from fresh specimens from autopsy or surgery will be made with a unique apparatus which permits automated scanning of multiple regions. In addition to scattering measurements, attenuation will be measured using a radiation force balance. Scattering will be normalized using attenuation and system parameters to obtain average differential scattering cross section as a function of angle and frequency and also to yield total scattering cross section as a function of frequency. These two intrinsic properties of tissue will provide important descriptions of scatterer sizes and spacings which can be affected by disease. The angle and frequency dependence of average differential scattering cross section will be used to calculate the individual contributions to scattering due to compressibility variations, density variations, and correlation between compressibility and density. The calculations will be carried out over a window of lengths determined by the range of frequencies and angles employed in the measurements to yield intrinsic ultrasonic descriptions of tissue composition which are not available. Acoustic data will be linked to structures in cross sections of corresponding volumes by using a newly developed analysis which permits conversion of scattering from two-dimensional regions to scattering from three-dimensional regions. Normal and abnormal tissues from liver, spleen, breast, and pancreas will be studied. The ability of the various measured and calculated ultrasonic data to characterize tissue will be evaluated using gross specimen descriptions and histologic evaluations of sections as the standard. The results are expected to provide a foundation for a significant increase in diagnostic utility of ultrasound from quantitative intrinsic acoustic parameters of tissue that can be employed to distinguish between normal and diseased tissue and also to determine the severity of disease in circumstances not currently possible.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
1R01CA039516-01
Application #
3178581
Study Section
Diagnostic Radiology Study Section (RNM)
Project Start
1985-04-01
Project End
1988-03-31
Budget Start
1985-04-01
Budget End
1986-03-31
Support Year
1
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of Rochester
Department
Type
DUNS #
208469486
City
Rochester
State
NY
Country
United States
Zip Code
14627
Waag, R C; Astheimer, J P; Smith 3rd, J F (1992) Analysis and computations of measurement system effects in ultrasonic scattering experiments. J Acoust Soc Am 91:1284-97
Waag, R C; Demczar, B A; Case, T J (1991) Nonlinear receiver compression effects on the amplitude distribution of backscattered ultrasonic signals. IEEE Trans Biomed Eng 38:628-33
Waag, R C; Astheimer, J P (1990) Characterization of measurement system effects in ultrasonic scattering experiments. J Acoust Soc Am 88:2418-36
Waag, R C; Dalecki, D; Smith, W A (1989) Estimates of wave front distortion from measurements of scattering by model random media and calf liver. J Acoust Soc Am 85:406-15
Waag, R C; Dalecki, D; Christopher, P E (1989) Spectral power determinations of compressibility and density variations in model media and calf liver using ultrasound. J Acoust Soc Am 85:423-31
Sinai, J; Waag, R C (1988) Ultrasonic scattering by two concentric cylinders. J Acoust Soc Am 83:1728-35
Parker, K J; Lerner, R M; Waag, R C (1988) Comparison of techniques for in vivo attenuation measurements. IEEE Trans Biomed Eng 35:1064-8
Witten, A; Tuggle, J; Waag, R C (1988) A practical approach to ultrasonic imaging using diffraction tomography. J Acoust Soc Am 83:1645-52
Lerner, R M; Waag, R C (1988) Wave space interpretation of scattered ultrasound. Ultrasound Med Biol 14:97-102
Parker, K J; Asztely, M S; Lerner, R M et al. (1988) In-vivo measurements of ultrasound attenuation in normal or diseased liver. Ultrasound Med Biol 14:127-36

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